Answer:
y = - 3x + 12
Step-by-step explanation:
Slope intercept form of line
y = mx + b where m = slope, b = y-intercept
==> y = -3x + b is the equatin
To find b, plug in values for point x = 9, y =-15 and solve for b
-15 = -3(9) + b
-15 = -27 + b
Add 27 both sides
-15 + 27 = b
12 = b
b = 12
Equation is
y = - 3x + 12
